No, sorry. And even if it were, they don't have good characteristics for tracking. No Track feat, and poor modifiers for the relevant skill checks.

The DC for the trail is higher than 10, which means that characters who lack the feat can still use Survival and Search to detect individual traces of a creature's passage through an area (which is how Vex found something).

You have NPC resources on hand who can handle tracking (Mbali and Uluwasi both have ranger levels).

The real challenge is that you have a casualty who is now a mobility problem. Fanyana can only move at half speed, and his blindness imposes some gnarly penalties to most Str and Dex-based skills. He'll be a liability if you take him with you, but if you leave him behind, he's a sitting duck.

Knowledge (nature):
Vexandi thinks that Sibusiso's odd behavior certainly sounds like the kind of thing that a fey might cause, although he thinks it's a little odd that one should be hunting where there is no clear territorial basis for its attacks. This cavern was inhabited until fairly recently, and the only spiritual activity he's detected is that haunting in what's left of the kobolds' old chapel. But if he could figure out a way to put that aside, then really this sounds like exactly the kind of thing that a fey would do—blinding one mortal and luring another off into the wilderness before anyone can respond is consistent with how they fight.

That still wouldn't explain why Fanyana was raving about a beautiful woman with snaky tentacles instead of arms, though. Vex is stumped.

Lore:
As Rasnak examines Fanyana's eyes (and determines that there's nothing he can do for the hob), he also listens to the blinded sentry's description of what happened outside. When Uluwasi asks what could have blinded Fanyana and induced Sibusiso to wander into the woods, the little kobold immediately concludes that it's a bothrian. They're relatively uncommon in these parts, but not unknown, and Rasnak is aware that some of them can suppress the will of individuals they've chosen as prey.

Since bothrians are grotesque crossbreeds of mollusk and insect stock with various other creatures, Rasnak doesn't feel as if he can guess exactly what lurks in the forest tonight. Whatever it is, it's got tentacles; bothrians always come across as a more-or-less recognizable hybrid of an octopus or assassin vine with some other creature.

He suspects that if Sibusiso is dead already, then the best possible outcome already has been achieved. Some bothrians . . . play . . . with their food.

Knowledge (nature):
Leland also concludes that he can't do anything for Fanyana. The hob's eyes are physically intact—in fact, the pupils dilate and contract normally when exposed to light. Fanyana ought to be able to see, but obviously can't.

He's heard about these symptoms in those who've gotten on the bad side of a nymph; they are reputed to be so striking in appearance that the mere sight of an angry nymph can destroy a mortal's vision. But this attack doesn't make sense for most nymphs; they're territorial but shy, and it seems extremely out of character for a nymph to attack someone who hasn't cornered it or placed its home in danger. That clearly cannot be the situation here, since the cavern was already settled by mortals and had then become deserted after the deaths of Rasnak's clan.

Then there's the matter of Sibusiso's disappearance. It isn't unheard of for them to take mortals as lovers, but Sibusiso was no beauty. And it'd hardly make sense for her to blind someone who is clearly friends with her prospective mate, although Leland supposes that an evil nymph, such as those that associate with the Unseelie Court, might not care.

But then again, Leland also supposes that an Unseelie nymph may take a humanoid as food. They're nasty creatures, and a hungry one can be nastily indiscriminate about the source of its meat.

With more people going than staying, Rasnak realizes that he's perhaps safer hiding among the crowd than sitting in the cave alone. He will also reluctantly go -- after trying to talk them all out of it, of course.

It's a bothrian. There are lots of different kinds, and they're not natural. The popular theory is that some wizard in the more isolated parts of Enteria's temperate rainforests must have created them, either by accident or as some kind of perverse experiment. Rasnak thinks that he probably doesn't really want to see one in person, since they're rumored to be crossbreeds that include several species at a time: a touch of mollusk and a smidge of insect or arachnid, usually swirled together with some unfortunate mammal or avian. From Fanyana's testimony, it sounds like this one included something basically shaped like a humanoid female.

Anyway, Rasnak's impression of them is that most are infertile in much the same way as a mule or other hybrid. That's unquestionably a good thing. Nevertheless, some of them have demonstrated the ability to reproduce, and Sibusiso's injuries suggest that the one that killed him retained some kind of interest in procreation. Rasnak has no way of knowing for sure whether he's looking at the aftermath of a feeding, a mating, or both.

Okay, let's have a round of Listen checks from everybody, please. Also, is anyone going to volunteer to take the lead in this murk? Any In Character preferences about your marching order? Mbali and Uluwasi are pretty lax about such things.

Dafyd's having some issues on his end that prevent him posting here because he's in Greenland at the moment, and the sun's messing up certain parts of his Internet service. But we're in touch via other means, so this is his roll.

If all you and the creature/NPC can do is hear one another rustling around in the fog? I mean, I guess that technically this is a surprise round of a sort. I guess. Maybe.

I haven't called for initiative, because although you now know there's something out there, you can't see it and don't really know exactly where it is. So it seems premature to worry about whose turn it is to act.

Right now, the situation is apparently that if you stay on the track, your path is likely to lead pretty close to the source of the noise. On the other hand, this thick fog makes it super easy to get lost; if you leave the path to try to keep your distance from whatever Evrinel has heard splashing around, then you have no landmarks to use to orient yourselves. You may not be able to find the road again.

To clarify the mechanics here, leaving the road without getting lost will require a DC 15 Survival check. That's no big deal as long as you're all convoyed up the way you are at present; under conditions that allow you to take 10 on a Survival check to avoid becoming lost, Mbali and Uluwasi can't possibly fail. For that matter, neither can Vexandi or Leland. As long as you're clumped together and aren't threatened or rushed, there really is no appreciable chance that you'll get lost.

But if something happens to separate some of you from the group, you're going to have to fend for yourselves. And in the current circumstances, the "something" that happens will probably be that a monster jumps out of the fog and tries to eat you. You won't be able to take 10 in that case. Not good.

Even worse, if you become lost, you won't realize it unless you make a DC 20 Survival check. Until you do, you'll wander at random. Eventually you'll get your bearings, but it could take hours, and that's a long time to be wandering alone. Something bad could very well happen to you.

Worst of all, if you get lost here you are in conditions that make it far more likely that your predicament will be aggravated by other factors. The presence of fog, the prevalence of of creeks and streams, and the likelihood that you'd be wandering around in this mess at sunset are all indicators that you could get sucked into the Spirit World.

In all probability you would NOT get lost unless the splashing noises are coming from something that 1) is hostile, 2) knows you're there, and 3) is so frightening that the entire expedition flees in a panic.

But if you do, it could go spectacularly wrong. As a DM, I'm getting a little turned on just thinking about it.

It blows my mind that many forms of dwarfism that occur in the real world affect bone length but not soft tissue. As a result, Little People are hung just like people without dwarfism; but PROPORTIONALLY that makes them huge. If I had dwarfism, that's how I'd start most conversations.

It can't see us in the fog, so I'm for hiding, too. If we stay still maybe it'll wander off after a few minutes. I think we should at least try that. Then, when it fails, we can all scatter and meet up in the fairy realm.

Johten will do whatever Mbali orders, but he's most in favor of keeping ready while slowly moving forward, the better to (maybe) put some distance between us and what/whoever is making noise. It could be a trash panda. It could be an owlbear. It could be a vengeful spirit in the form of an ever-changing collection of random geometric shapes, interested only in existing outside the window of its estranged father and whispering ominously of all his sins. Johten would rather not find out.